Multiple cylinder engine construction



Feb. 27, 1934. D. J. DOLAN 1,949,043

MULTIPLE CYLINDER ENGINE CONSTRUCTION Filed Jan. 10. 1931 3 Sheets-Sheet l f? g I INVENTOR v ATTORNEY.

Feb. 27, 1934. D. J, DOLAN MULTIPLE CYLINDER ENGINE CONSTRUCTION Filed Jan. 10. I5 Sheets-Sheet 2 INVENTOR ATTO NEY! Feb. 27, 1934. D J DOLAN MULTIPLE CYLINDER ENGINE CONSTRUCTION Filed Jan. 10 1931 I5 Sheets-Sheet 3 INVENTOR Patented Feb. 27, 1934 MULTIPLE CYLINDER ENGINE CONSTRUCTION David J. Dolan, Cleveland Heights, Ohio Application January 10, 1931. Serial No. 507,780

5 Claims.

This invention relates to multi cylinder internal combustion engines and more specifically to a novel disposition of the parts, particularly the cylinders thereof whereby the proportional dimensions of the engine result in improved adaptability for aircraft.

An object of the invention is, therefore, to provide a multiple cylinder engine construction wherein the head dimensions are wide but not high, and the depth is not great, so that the engine may be conveniently located to extend within the wing structure of an aeroplane.

Another object is to provide an engine structure adapted to have relation with the framework of the aeroplane so that the two may comprise an integral unit.

Still another object of the invention is to provide engine structure and particularly cylinder structure which shall combine rigidity with light weight; and to this end to provide that the cylinders need not be of the usual cast metal, and a characteristic of the engine be small bore and long stroke.

A further object of the invention is to pro vide structure wherefrom the engine operating stresses are entirely confined within the engine itself; and particularly wherein the reciprocating masses have inherent balance.

The exact nature of the invention together with further objects and advantages thereof will be apparent from the following description taken in connection with the accompanying drawings, in which Fig. 1 is a plan view largely in section however, showing one end of an engine constructed according to my invention; Fig. 2 is a plan view of the opposite end of the same; Fig. 3 is an end elevation of pertinent parts of the invention showing the cylinders thereof in section; Fig. 4 is a corresponding end elevation with the cranks in a different position, parts being broken away to show details of construction; Figs. 5 and 6 structure of an aeroplane as will appear.

are respectiye views of an aeroplane in which the engine is incorporated, Fig. 5 showing parts of the plane broken away so that engine structure appears in perspective.

With reference now to the drawings the engine has a horizontal crank shaft 1 with oppositely disposed cranks 2 thereon, the crank being mounted in suitable bearings carried by a substructure A, which may be a part of the frame Above and below the crank shaft as shown in Figs. 3 and 4, and beyond the cranks thereof as shown in Figs. 1 and 2 are located cylinders 3 waterjacketed as indicated. Each of these cylinders has a central head portion 4, so that the crank shaft 1 is disposed in the plane of these four head portions 4. The ends of the cylinders 3 are open, and a piston 5 is arranged in each end of each cylinder. Thus eight expansible chambers are formed, two for each cylinder 3, one on each side of the head portion 4 thereof. Opposite each end of each cylinder 3 and aligned therewith is another cylinder 6. Each cylinder 6 has a head portion 7 on its remote end, and a piston 5 similar to the pistons 5 of the cylinders 3. the piston of each cylinder 6 and the adjacent one of the corresponding cylinder 3 is a cylindrical spacer 8, and the pistons at the ends of the spacer are secured thereagainst by a piston rod within the spacer 8. Extending parallel with the crank shaft 1 between each corresponding pair of piston rods 9 is a cross head member 10. A connecting rod 11 joins each cross head 10 with one of the cranks 2. vAs indicated Figs. 1 and 2 preferably one of the cranks 2 is located in a central vertical plane, and the other crank is in the form of two smaller cranks on either side of the central one. Thus on one side of the engine there will be two connecting rods 11 as indicated Fig. 2. Also since for each crank pin there are two cross heads 10 one of the cross heads is directly joined with its crank by the connecting rod 11 as in Fig. 3 and the other corresponding connecting rod 11a is joined as at 12 with its mated connecting rod instead of directly to its crank pin. The proportions and arrangement of the parts is such that when the crank shaft is in the position of Fig. 4 with the connecting rods crossed as indicated, the pistons 5 of the cylinders 3 will be in their head end positions, adjacent the head portions 4; and when the crank shaft is moved to the position shown in Fig. 3 the pistons 5 of the other cylinders 6 will be at the head ends of their stroke adjacent the cylinder head portions 7 as indicated Fig. 1; and it will be noticed that the engine is proportioned to have a very long stroke for its bore. By the cylinder arrangement described the pistons are relieved of substantially all side thrust in their cylinders. The cross head members 10 extend beyond the planes of the cylinders and carry at their ends shoes 13 movable along suitable stationary ways 14 rigidly mounted on the substructure A.

Between Each of the cylinders 6 is secured at its head yet the engine as a unit is secured with the substructure at a number of points so as to be mutually reinforced therewith.

The engine is intended to operate upon the two stroke cycle and particularly the cycle described in my copending application, Serial No. 350,425, filed March 27, 1929, so that a source of air supply under pressure is needed. Therefore, adjacent the head ends of the cylinders 7 at each end of the engine I provide an air cylinder 15. Thus, the cylinder 15 being joined directly with the power cylinder 6 greatly adds to the rigidity of the entire structure. Within each cylinder 15 is a transverse wall 16 providing a chamber 17 which chamber is in communication with the adjacent cylinder head 'I by suitable valves 18. Beyond the wall 16 is a piston 19 having a piston rod 20 joined as indicated with the near cross head 10. The length of the cylinder 15 is such as to accommodate a stroke of the piston 19 equal to that of the working pistons 5. The air pump arrangement is such that the pistons 19 will be double acting, that is, so that there will be discharge into the receiver 17 during each stroke of the pump. Thus an automatic valve 21 may be located in the Wall 16 and piping 22 including an automatic valve 21a may connect the receiver with the far end of the cylinder 15 and with the head portions 4 of the cylinders 3. I Liquid fuel is fed to the cylinder heads through piping 23 leading from a distributor 24 and the distributor receives fuel under pressure from a suitable fuel pump.

Piston rods 9 are provided with leads 25 communicating with the leads 26 in the cross head member 10. The leads 26 receive cooling liquid from a pump 27 through a suitable plunger device 28. The annular hollows about the piston rods have exit by leads 29 and plunger tubes 30 cooperating with cylinders 31. Thus cooling circulation for the pistons will be from the pump 27 through the leads 26, the hollow piston rods to the insides of the piston heads, thence out through the leads 29, tubes 30 and cylinders 31.

It will be apparent that the engine is wide but neither high, nor deep in the direction of the crank shaft. Thus as appears from Figs. 5 and 6, the engine is admirably adapted for incorporation in an aeroplane, the propeller 32 of which may be mounted directly upon the forward end of the crank shaft 1, the shaft extending back into the fuselage and the cylinders extending laterally within the wings of the aeroplane.

What I claim is:

1. In an engine of the class described, a pair of parallel cylinders, a crank shaft extending between said cylinders adjacent head portions thereof, a second pair of cylinders one aligned with each of said first named pair, pistons for said cylinders, piston rods joining the pistons of each aligned pair of cylinders, and connecting rods joining said piston rods with the crank of said shaft.

2. In an engine of the class described, a pair of parallel cylinders having head portions intermediate their lengths, a crank shaft extending between said cylinders adjacent said head portions thereof and having a pair of oppositely disposed cranks, an aligned cylinder opposite the mouth of each of the first named cylinders, a piston for each of said cylinders, piston rods joining the pairs of adjacent aligned pistons, and connecting rods each joining one of said piston rods with one of said cranks.

3. In an engine of the class described, a plurality of banks of cylinders, each bank having two parallel lines of cylinders, each line of cylinders including a cylinder with a central head portion, a crank shaft extending in the plane of said head portions between the lines of cylinders and having cranks between the banks, a piston for each cylinder, piston rods for the pistons, cross heads joining corresponding piston rods of the two banks, and connecting rods joining the cross heads with cranks of the crank shaft.

4. In an engine of the class described, a plurality of banks of cylinders, each bank having two parallel lines of cylinders, each line of cylinders including a cylinder with a central head portion, a crank shaft extending in the plane of said head portions between the lines of cylinders and having cranks between the banks, a piston for each cylinder, piston rods for the pistons, cross heads joining corresponding piston rods of. the two banks and extending beyond the banks, ways for said cross heads at the ends of the latter, and

connecting rods joining the cross heads with the cranks of the crank shaft.

5. In an engine of the class described, a plurality of parallel cylinders, pistons for said cylinders, piston rods for said pistons, crosshead means joining said piston rods, a crank shaft, connecting rod means joining said crosshead with the crank of said crank shaft, and an air pump arranged to serve said cylinders and having a cylinder and a piston, said pump cylinder being of greater diameter than said engine cylinder and l'.

arranged to overlie the heads of a plurality of said engine cylinders to rigidly connect the latter and discharge directly thereto, and a piston rod for said pump piston extending between said engine cylinders and connected with said crosshead.

DAVID J. DOLAN. 

